PS9-12. Comparison of Fecal Microbial Composition and Plasma Metabolome Between Dairy and Meat Goats.

Abstract Dairy and meat goats exhibit breed-specific physiological differences that are associated with changes in their gastrointestinal microbiome and plasma metabolome. This study aimed to characterize differences in the fecal microbiome and whole plasma metabolome of growing dairy and meat goats. Twenty Alpine (n = 10; 64.4± 5.28 kg) and Spanish (N = 10; 61.9±4.59) yearlings arranged by age, body weight, and body condition score and allocated for 70 days in a randomized continuous feeding trial (Vytelle System) with a commercial diet were used (16% CP, 35% NDF, 15% ADF). Weekly, the Dry matter intake (DMI), body weight (BW), feed efficiency (FE), Average daily gain (ADG), and Body condition (BCS) score were calculated. Fecal and plasma samples were collected weekly, placed in sterile bags, and stored at - 80 °C for microbiome analysis (16s RNA sequencing) and whole-plasma untargeted metabolomics. The model included the fixed effects of Breed, Week, and Their Interactions, as well as the random effect of the animal. Microbial indexes (alpha and beta), principal coordinate analysis (PCoA), and LEfSe were estimated to identify the differentially abundant taxa. There were no differences (P > 0.05) between dairy and meat goats in terms of DMI (1.51 vs. 1.61 kg/d), ADG (220 vs. 156 g/d), FE (0.15 vs. 0.1 kg BW/ kg DMI), and BW (72.4 vs. 69.4 kg). However, BCS was higher. (P < 0.01) in meat goats compared to dairy goats (4.88 vs. 4.54). No differences in alpha diversity between dairy and meat goats were observed (P = 0.15), but differences were observed in beta diversity between treatments (P < 0.01). The ANOSIM revealed that Prevotellaceae UCG_004 and Lachnospiraceae families were enriched (P < 0.05) in dairy goats. In contrast, Prevotellaceae UCG_001 and Fibrobacter families were enriched (P < 0.05) in meat goats. Plasma metabolomics revealed 47 differentially expressed metabolites between dairy and meat goats. Both amino acids and organic acids metabolism were differentially expressed (P < 0.05) in dairy goats, whereas lipid metabolism was differentially expressed (P < 0.05) in meat goats. Collectively, this study showed that carbohydrate metabolism and lipid metabolism between dairy and meat goats are associated with breed-specific gut microbial composition. .